Pallet boxes are strong and tough. They are used for a diverse range of heavy-duty storage solutions in both agri-food and non-food industrial environments, where they are frequently called upon to carry individual unit loads weighing up to 500Kg and then stacked many units high.
Plastic pallet box strength will be constrained by the method of handling, the products they are carrying and temperature. This article looks at the factors you need to consider when selecting a bulk container for heavy-duty use, helping you to prevent accidents and avoid breakage.
What is a Plastic Pallet Box?
Plastic pallet boxes combine a pallet base with solid or ventilated sides, which are either rigid or folding to save space on return transport. Most models have a standard UK pallet footprint of 1200 x 1000mm, with Euro (1200 x 800mm) and half Euro (800 x 600mm) sizes also popular.
Plastic pallet boxes are usually manufactured in HDPE (high-density polyethene) or PP (polypropylene); materials noted for their mechanical strength and chemical resistance. They are known by many different names throughout industry, including plastic bulk boxes, plastic stillages, large bulk containers and Dolavs.
Various loading specifications need to be considered when selecting a plastic pallet box:
The “unit load” is the maximum weight an individual container can carry. Loading figures usually refer to a uniformly distributed load (UDL) so you need to beware of concentrating the load on one area (point loading), as this could reduce the strength or stability of the container.
Plastic folding bulk containers usually have a similar maximum unit load to rigid models; however, this assumes that the load is concentrated on the base of the container. Small loose items, such as metal fixings, will place a large lateral force on the sides that may exceed the capability of a folding unit. Talk to the supplier to ensure that your chosen folding pallet box is up to the job.
Plastic rigid bulk containers are extremely robust and their sides provide excellent lateral strength, so they are ideal for bulk handling of small and heavy loose items. Many solid models can be fitted with drainage taps for liquid storage. Containers filled with liquid should remain static and must be placed on a spill control pallet or bunded if used for any form of hazardous fluid.
The “stacked load” is when containers are placed on top of another, allowing loaded containers to be stacked sometimes up to ten units high. The stated maximum stacked load will assume that containers are placed on a flat surface, so uneven or sloping ground should be avoided or the loading and stack height reduced. As the combined weight of the loaded bulk containers is likely to exceed several tonnes, it is also important to ensure that the surface they stacked on can also support the load.
Select pallet boxes that securely interlock when stacked and have wide-width fork entry slots for easier and faster forklift access.
The “dynamic load” refers to moving loaded containers by forklift or other mechanical handling equipment. For speed and efficiency containers should be capable of being moved when stacked two or three high, so check that the manufacturer’s specifications specify a dynamic load of at least double the static load, and that containers securely inter-stack for safe handling operations.
Use on Pallet Racking
The “racking load” refers to storing plastic pallet boxes on pallet racking supported by beams. Unless the pallet racking is boarded (and the boarding can carry the weight) or fitted with skid channels, only pallet boxes with runners should be used. Three-runner models must be placed on racks with the runners at 90º to the beams and there should be an even overhang front and back.
Operating temperature should also be considered because at lower temperatures impact resistance will be reduced, while at higher temperatures load capacity may decrease. As most testing is conducted at ambient temperatures, users should consult the manufacturer for operations approaching maximum load in fridges and freezers or in hot environments such as foundries or distribution to warehouses in southern Europe.
Ventilated rigid bulk containers are ideal for food storage in fridges and freezers. The ventilation holes promote air circulation, helping the contents to quickly get down to the desired temperature. If you’d like to find out more about how Totebox can help you, get in touch today, we’d love to hear from you. Give us a call on 01327 340177 or pop us an email at email@example.com.